Port Otago has received resource consent from the Otago Regional Council to continue to use three marine sites adjacent to beaches to dump spoil from its routine channel dredging maintenance programme.
Local surfers, concerned the nationally recognised Aramoana beach break could be affected, and Te Runanga o Ngai Tahu, were successful in having extra monitoring imposed in several areas, and had the length of the consent time reduced from 35 to 25 years.
Most concerns were raised by Dunedin's surfing community and scientists, on behalf of the iwi.
The ORC appointed a hearing committee, which looked at the issue between November and January, including site visits, and released its decision last week.
The hearing committee noted there was ``no significant opposition'' and that Port Otago had delivered a ``comprehensive assessment of the environmental effects'', and later agreed to extra conditions.
Five parties supported the application, with three heard at the hearing, a sixth gave support, on conditions, one was neutral and one person opposed, but did not want to be heard.
The three sites are Heyward Point, where spoil has been dumped since 1865, off Aramoana spit, since 1986, and Shelly Beach, since 1987.
Port Otago has for the past three years been allowed to use the sites under a three-year consent, while it consulted with the community in seeking the longer, 35-year term.
Port Otago's resource consent to dump spoil at sea, for its Next Generation project to deepen and widen the shipping channel between Port Chalmers and Taiaroa Head is separate, and was granted in 2012, allowing up to 7million cu m of spoil to be dumped 10km offshore from Taiaroa Head.
At Heyward Point the disposal area will be increased from 40ha to 225ha, with no more than 300,000cu m to be dumped over any five-year period.
Aramoana's disposal area would increase from 28ha to 36ha, with only 100,000cu m of sand to be dumped over any five-year period.
At Shelly Beach, up to 50,000cu m of sand only could be dumped per year, primarily for beach renourishment.
St Clair surfing club South Coast Boardriders Association supported the application, but with reservations about the disposal volumes, but new conditions agreed to appeased the club, with more emphasis on sampling during the early years of the consent.
Marine ecologist Dr Daniel Pritchard, employed by Te Runanga o Ngai Tahu, supported the application, while Timothy Vial, a planner employed by Kai Tahu ki Otago, also supported the application, but with conditions including ecological monitoring for five years, plus reviews and development of an inshore dredging management plan.
Another condition was included, and accepted by Port Otago, that extra benthic monitoring be undertaken, at five-yearly intervals towards the latter stages of the 25-year consent.
One of several expert witnesses for Port Otago was oceanographer Dr Peter McComb, who investigated wave and sediment dynamics, including field measurements, validation of numerical models for waves, currents and sediment transport.
An adaptive management regime aimed to conserve the functional features responsible for the high-quality surf breaks at Aramoana and Whareakeake.
On the question of any effects on the benthic (bottom-dwelling marine communities) Dr Graham Fenwick said there were 265 species recorded, which were common up and down the South Island's east coast.
He suggested intensive sampling be carried out every two years, for the first six years, to determine if there were any changes between the control and actual disposal site.
Port Otago has agreed to monitor kelp beds in Blueskin Bay, where there were paua and kina, in case there were adverse events.
Port Otago chief executive Geoff Plunket was asked whether the port company was considering an appeal over any aspect of the decision.
``We're naturally pleased to have the consent confirmed for the next 25 years,'' Mr Plunket said.
The decision was being reviewed by Port Otago's advisers, to check the conditions were acceptable, with a decision due shortly, he said.
